If both the CSRF validation and the Session state is turned off, the pages containing AsyncUpload control will throw a null reference exception.

<appSettings>
  <add key="Telerik.AsyncUpload.EnableCsrfValidation" value="false" />
</appSettings>
<system.web>
  <sessionState mode="Off" />

Telerik UI for ASP.NTE AJAX nuget package adds ChartImage handler configs to Web.Config (system.web/httpHandlers and system.webServer/handlers) even though it does not support RadChart any more.

Also it seems to mess system.webServer/handlers configuration by adding remove actions for other Telerik handlers AFTER add actions.

system.web/httpHandlers before:

    <httpHandlers>
      <add path="Telerik.Web.UI.SpellCheckHandler.axd" type="Telerik.Web.UI.SpellCheckHandler" verb="*" validate="false" />
      <add path="Telerik.Web.UI.DialogHandler.aspx" type="Telerik.Web.UI.DialogHandler" verb="*" validate="false" />
      <add path="Telerik.RadUploadProgressHandler.ashx" type="Telerik.Web.UI.RadUploadProgressHandler" verb="*" validate="false" />
      <add path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource" verb="*" validate="false" />
    </httpHandlers>

system.web/httpHandlers after:

    <httpHandlers>
      <add path="Telerik.Web.UI.SpellCheckHandler.axd" type="Telerik.Web.UI.SpellCheckHandler" verb="*" validate="false" />
      <add path="Telerik.Web.UI.DialogHandler.aspx" type="Telerik.Web.UI.DialogHandler" verb="*" validate="false" />
      <add path="Telerik.RadUploadProgressHandler.ashx" type="Telerik.Web.UI.RadUploadProgressHandler" verb="*" validate="false" />
      <add path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource" verb="*" validate="false" />
    <add path="ChartImage.axd" type="Telerik.Web.UI.ChartHttpHandler" verb="*" validate="false" /></httpHandlers>

system.webServer/handlers before:

    <handlers>
      <add name="Telerik_Web_UI_SpellCheckHandler_axd" path="Telerik.Web.UI.SpellCheckHandler.axd" type="Telerik.Web.UI.SpellCheckHandler" verb="*" preCondition="integratedMode" />
      <add name="Telerik_Web_UI_DialogHandler_aspx" path="Telerik.Web.UI.DialogHandler.aspx" type="Telerik.Web.UI.DialogHandler" verb="*" preCondition="integratedMode" />
      <add name="Telerik_RadUploadProgressHandler_ashx" path="Telerik.RadUploadProgressHandler.ashx" type="Telerik.Web.UI.RadUploadProgressHandler" verb="*" preCondition="integratedMode" />
      <add name="Telerik_Web_UI_WebResource_axd" path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource" verb="*" preCondition="integratedMode" />
    </handlers>

system.webServer/handlers after:

    <handlers>
      <add name="Telerik_Web_UI_SpellCheckHandler_axd" path="Telerik.Web.UI.SpellCheckHandler.axd" type="Telerik.Web.UI.SpellCheckHandler" verb="*" preCondition="integratedMode" />
      <add name="Telerik_Web_UI_DialogHandler_aspx" path="Telerik.Web.UI.DialogHandler.aspx" type="Telerik.Web.UI.DialogHandler" verb="*" preCondition="integratedMode" />
      <add name="Telerik_RadUploadProgressHandler_ashx" path="Telerik.RadUploadProgressHandler.ashx" type="Telerik.Web.UI.RadUploadProgressHandler" verb="*" preCondition="integratedMode" />
      <add name="Telerik_Web_UI_WebResource_axd" path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource" verb="*" preCondition="integratedMode" />
    <remove name="ChartImage_axd" /><remove name="Telerik_Web_UI_SpellCheckHandler_axd" /><remove name="Telerik_Web_UI_DialogHandler_aspx" /><remove name="Telerik_RadUploadProgressHandler_ashx" /><remove name="Telerik_Web_UI_WebResource_axd" /><add name="ChartImage_axd" path="ChartImage.axd" type="Telerik.Web.UI.ChartHttpHandler" verb="*" preCondition="integratedMode" /></handlers>

Regression introduced in: 2025.4.1111

When RadEditor is in HTML mode, calling get_html() without parameters modifies self-closing tags in the returned content.

According to the documented API behavior, the RadEditor client filters should modify the returned content only when the isFiltered argument is set to true. However, the content is currently passed through browser DOM serialization even when filtering is not requested. This normalizes HTML void elements and removes the XHTML self-closing slash.

Steps to reproduce

1. Add a RadEditor to a page.
2. Switch the editor to HTML mode.
3. Enter the following content:

<img alt="" src="image.png" />

4. Call editor.get_html() or editor.get_html(false).

Actual result

The returned markup is modified and the self-closing slash is removed:

<img alt="" src="image.png">

Expected result

When filtering is not requested, the content entered in HTML mode should be returned without filter-related DOM serialization:

<img alt="" src="image.png" />

Calling editor.get_html(true) may modify the returned content according to the enabled RadEditor client filters.

Impact

Applications that store, compare, validate, or further process XHTML-compatible markup may receive content different from the source entered by the user. This can affect integrations that rely on self-closing tag syntax.

Hovering over the RadMenu sub-item toggle arrow icon does not expand its sub-item.

Can be reproduced with the following configuration:



<telerik:RadMenu ID="RadMenu2" _OnClientLoad="OnClientLoad" runat="server" RenderMode="Auto" ShowToggleHandle="true">
    <Items>
        <telerik:RadMenuItem Text="Main Menu">
            <Items>
                <telerik:RadMenuItem Text="Item 1">
                    <Items>
                        <telerik:RadMenuItem Text="Sumbenu 1"></telerik:RadMenuItem>
                        <telerik:RadMenuItem Text="Sumbenu 2"></telerik:RadMenuItem>
                    </Items>
                </telerik:RadMenuItem>
                <telerik:RadMenuItem Text="Item 2">
                    <Items>
                        <telerik:RadMenuItem Text="Sumbenu 3"></telerik:RadMenuItem>
                        <telerik:RadMenuItem Text="Sumbenu 4"></telerik:RadMenuItem>
                    </Items>
                </telerik:RadMenuItem>
            </Items>
        </telerik:RadMenuItem>
    </Items>
</telerik:RadMenu>



Workaround:

                <script>
                    var menuItem = null;
     
                    function OnClientLoad(sender) {
                        $telerik.$(".rmToggle,.rmToggle *").on("mouseover", ExpandMenu);
                    }
                    function ExpandMenu() {
                        var item = $telerik.$(this).closest('.rmItem')[0]._item
                        if (!item.get_isOpen()) {
                            item.open()
                        }
                    }
                </script>

The RadEditor Add Link dialog uses HTML tables for layout, but the tables are exposed with data-table semantics.

The dialog contains:

• An outer reControlsLayout table
  
• A nested reConfirmCancelButtonsTblLight table for the action buttons
  
• Hidden <caption>, <thead>, and <th> elements intended to describe the tables
  
• No role="presentation" or role="none" on the layout tables
  

Because these tables are used to arrange form fields and buttons rather than display tabular data, screen readers and automated accessibility tools may interpret them as data tables. The hidden headers are removed from the accessibility tree and do not provide useful table semantics. The nested table may also result in redundant or confusing table announcements.

This causes WCAG 2.1 accessibility findings related to table semantics, including F49 and F91 under Section 508.

RadGrid’s SEO Paging activates for normal users in the latest Brave browser, because sessions are misclassified as crawlers (Request.Browser.Crawler evaluates to true).

Even with PagerStyle.EnableSEOPaging set to False, SEO paging still turns on due to crawler detection, and ask whether the legacy Request.Browser.Crawler approach should be removed for ASP.NET WebForms in Telerik.

When EnableSEOPaging is True, query string paging is always used, but when False, the grid still enables SEO paging upon crawler detection, which is being incorrectly triggered in Brave.

The Bold, Italic, Underline, Justify, Indent, Outdent and other commands are not localized in the Undo/Redo dropdowns.

Screenshots:

https://www.screencast.com/t/YLNTiPP7LAk

https://www.screencast.com/t/DS9Y6GrB 


Can be seen at http://demos.telerik.com/aspnet-ajax/editor/examples/localization/defaultcs.aspx. 

If you type 15 into the font size combo box and click away, a Javascript error is thrown and the font size of the selected cell does not change. If instead you type 16 and click away, the cell changes correctly. 16 is an option in the drop-down but 15 is not.

Error message:

RadSpreadsheetScripts.js:196 Uncaught TypeError: Cannot read property 'get_text' of null


The font size combo box works correctly in the Kendo spreadsheet demo (both with the current and the 2017.1.124 Kendo version ). You can also press enter to commit your typed font size in the Kendo widget, but not in RadSpreadsheet.

Steps to reproduce:
1. Open https://demos.telerik.com/aspnet-ajax/spreadsheet/examples/overview/defaultcs.aspx
2. Click inside the font -size dropdown
3. Type 15 and click outside the SpreadSheet

Result: A JavaScript error is thrown.

Good morning,

we have a strange issue using RadGrid with horizontal scroll and frozen columns: there a resizing of the height which gets user experience not the best.

See attached gif.

Could you please help us?

Please create a method that will convert the old expressions to new format and make them re-usable again.

In the demo:
https://demos.telerik.com/aspnet-ajax/editor/examples/trackchanges/defaultcs.aspx

1. (Preparation) Disable TrackChange and Remove all text. Enable Track Change back.

2. Insert table, (HTML View)

3. In the design mode set new paragraph after table:

Insertion of the table dissapeared.

How to fix this issue?

1. Open the demo page linked above.
2. Scroll down to the bottom of the RadListBox using only the mouse wheel.
3. Click on any item (e.g., "USA") to select it.

• The issue does not occur if the user clicks and drags the scrollbar thumb with the left mouse button before selecting an item.
• The issue does not occur if the user clicks the top or bottom navigation arrows on the scrollbar container to scroll.
• The unexpected reset to 0 only triggers when scrolling is performed exclusively via the mouse wheel prior to item selection.

Reproduction - http://somup.com/crVYIDot19

Setup to reproduce:

<telerik:RadContextMenu ID="RadContextMenu1" runat="server">
    <Targets>
        <telerik:ContextMenuDocumentTarget />
    </Targets>
    <Items>
        <telerik:RadMenuItem Text="item">
            <ItemTemplate>
                <asp:TextBox ID="TextBox2" runat="server" />
            </ItemTemplate>
        </telerik:RadMenuItem>
    </Items>
</telerik:RadContextMenu>

<telerik:RadButton runat="server" ID="RadButton2" Text="Postback" AutoPostBack="true" />

Steps to reproduce:

• Show the context menu with a right mouse click on the document.
• Type in a custom value in the TextBox embedded in the menu.
• Perform a postback by clicking on the RadButton.
• Show the context menu again. In the textbox, pick the autocomplete suggestion by the browser.

I'm using a RadTab and one of the RadPageViews starts with an RadAsyncUpload-Control. When I use arrow keys to select this tab and try to use the Tab-Key to focus the next element (the RadAsyncUpload in this case) nothing happens. If any other control (like a textbox) is placed above my upload control there is no problem focusing it.

You can see this in the attached Demoproject when using arrow keys to select to RpvUpload.

After updating to 2026.2 the layout of the SpinButton changed. To work around it, use the below CSS:

html body .RadInput .riUp,
html body .RadInput .riDown {
    height: 50%;
}

RadColorPicker remains clickable when its set_enabled(false) method is called.

Steps to reproduce:
1. Run this code:

        <telerik:RadColorPicker ID="RadColorPicker1" runat="server" ShowIcon="true" ShowEmptyColor="false" RenderMode="Lightweight" />
        <br /><br /><br />
        <select id="mySelect" onchange="EnableDisableColorPicker()">
            <option value="1">1</option>
            <option value="2" selected="selected">2</option>

        </select>
        <script>
            function EnableDisableColorPicker() {
                var x = document.getElementById("mySelect").value;
                var colorPicker = $find("<%= RadColorPicker1.ClientID %>");
                if (x == 1) {
                    colorPicker.set_enabled(false);

                } else {
                    colorPicker.set_enabled(true);

                }
            }
        </script>

2. Select option 1.

Result: RadColorPicker gets disabled, but remains clickable

When attempting to view the page in design view, here's what it looks like:

Here is the markup:

    <telerik:RadPanelBar ID="RadPanelBar1" runat="server">
        <Items>
            <telerik:RadPanelItem runat="server" Expanded="True" PreventCollapse="true">
                <HeaderTemplate>
                    <div ID="content-header">
                        Auditing Report | GPO Changes For User
                    </div>
                </HeaderTemplate>
                <ContentTemplate>
                    <div ID="content-body">
                        <telerik:ReportViewer ID="ReportViewer1" runat="server" ReportBookID="" Width="100%" Height="12in">
                        </telerik:ReportViewer>
                    </div>
                </ContentTemplate>
            </telerik:RadPanelItem>
        </Items>
    </telerik:RadPanelBar>